基于低碳减排的隧道水封爆破优化效果研究_周贤舜.pdf

第 20 卷 第 3 期2023 年 3 月铁道科学与工程学报Journal of Railway Science and EngineeringVolume 20 Number 3March 2023基于低碳减排的隧道水封爆破优化效果研究周贤舜1,4，张学民1,4，武朝光2,4，胡涛3，陈鑫磊1,4，段亚1,4(1.中南大学 土木工程学院，湖南 长沙 410075；2.中南大学 交通运输学院，湖南 长沙 410075；3.贵州省公路工程集团有限公司，贵州 贵阳 550008；4.中南大学 重载铁路工程结构教育部重点实验室，湖南 长沙 410075)摘要：为积极落实“碳达峰碳中和”战略，在隧道建设中，优化炮孔装药结构是钻爆法隧道实现绿色降碳的有效途径。通过现场试验和数值模拟对比研究水封爆破相对于常规爆破的降碳效果，并在工程实践中量化分析二者在碳排放评价上的优劣。首先，分析隧道爆破施工全过程的3个主要碳排放源，包括乳化炸药用量、风钻钻孔与炸药运输消耗的油品和通风降尘消耗的电力，并建立基于生产过程的隧道爆破碳排放计算模型。其次，通过有限元软件LS-DYNA分别建立空气、水与炸药轴向耦合爆破的数值分析模型，进一步探讨水封爆破破岩机理，由于水介质良好的低压缩性和更优的传能效率，水与炸药耦合装药结构加强了应力波正相作用时程和应力波峰值。因此，应力波叠加效应对岩体造成的损伤区域更大，岩体深部裂缝更加均匀。最后，依托贵州省董当特长隧道III级围岩试验段，根据隧道爆破碳排放计算模型核算了水封爆破和常规爆破的碳排放量。研究结果表明，炮孔内水垫层雾化降低了烟尘浓度从而通风时间仅需15 min左右，施工通风消耗的电力能源是爆破开挖碳排放的主要贡献源，而水封爆破节省的炸药用量次之。本案例中，水封爆破每循环进尺减少碳排放量约63.065 kgCO2 eq。本文研究成果可为相应隧道工程的绿色低碳减排优化提供参考。关键词：隧道工程；水封爆破；低碳减排；碳排放系数法中图分类号：U45 文献标志码：A 开放科学(资源服务)标识码(OSID)文章编号：1672-7029（2023）03-0996-12Optimization effect of tunnel water-decked blasting based on carbon emission reductionZHOU Xianshun1,4,ZHANG Xuemin1,4,WU Chaoguang2,4,HU Tao3,CHEN Xinlei1,4,DUAN Ya1,4(1.School of Civil Engineering,Central South University,Changsha 410075,China;2.School of Traffic&Transportation Engineering,Central South University,Changsha 410075,China;3.Guizhou Highway Engineering Group Co.,Ltd.,Guiyang 550008,China;4.Key Laboratory of Heavy-haul Railway Engineering Structure,Ministry of Education,Central South University,Changsha 410075,China)Abstract:A realistic technique to actively implement carbon neutrality and achieve green carbon reduction was 收稿日期：2022-09-15基金项目：国家自然科学基金资助项目(51978671)；湖南省研究生科研创新项目(CX20200366)通信作者：武朝光(1973)，男，山西平遥人，高级工程师，从事隧道工程专业的试验与科研工作；Email：DOI:10.19713/ki.43-1423/u.T20221801第 3 期周贤舜，等：基于低碳减排的隧道水封爆破优化效果研究to optimize the borehole structure when drilling and blasting tunnels.Field experiments and numerical simulations were used to compare the carbon reduction effect of water-decked blasting to traditional blasting.The pros and cons of each method in terms of evaluating carbon emission were quantified and compared in engineering practice.First,the three primary carbon emission sources of the tunnel blasting construction process were examined.The three main sources of carbon emissions were the usage of emulsified explosives in blasting,the utilization of oil to power drilling machinery and transport explosives,and the consumption of electricity to ventilate dust.Consequently,a carbon model was developed that considered three different types of carbon emissions produced over the entire tunnel construction process.Second,the numerical analysis was performed using the LS-DYNA program.Explosives coupled axially to the water(air)-deck were used in a single borehole blasting for the analysis.Further research was done on the mechanisms of rock breaking by water-decked blasting.The axial coupling charge structure of water and explosives enhances the stress wave positive phase and stress wave peak because water had a good low compressibility and greater energy transfer efficiency.As a result,the stress wave superposition created a bigger damage area to the rock and a more uniform fracture in the deep part of the rock.Finally,in order to evaluate the carbon emissions from two blasting techniques,the proposed carbon model was employed in the Dongdang Tunnel,a extra-long tunnel in Guizhou Province.The test segment was set up in the level III surrounding rock area of the tunnel.The findings indicated that water decking atomization in the borehole reduced the concentration of soot,resulting in a ventilation time of only about 15 minutes.The electric energy consumed by construction ventilation is shown to be the main contributor to the carbon emission of blasting excavation,while the quantity of explosives saved by water-seal blasting was shown to be the second largest.In this case,every cycle of tunnel excavation reduces carbon emissions by about 63.065 kgCO2 eq thanks to the water-decked blasting.As a result,the results can be used as the reference for lowering emissions in low-carbon,sustainable tunnel projects.Key words:tunnel engineering;water-decked blasting;carbon emission reduction;carbon emission coefficient method 我国的“碳达峰碳中和”战略对于交通工程是一场广泛且深入的技术变革。钻爆法在较长时间仍然是隧道建设中不可或缺的主要施工方法之一，迫切需要开展施工阶段的碳排放评价与技术优化，尤其需要以低碳绿色为方向指导隧道爆破技术的改进。钻爆法破岩的炮孔内炸药间隔充填不可压缩介质可均匀传递爆轰压力，在降低炸药单耗的同时可提高爆破效率1。其中，尤以低压缩性(近似不可压缩)的水介质应用最广24。炮孔内采用水介质和炸药2种不同介质轴向耦合爆破破岩的方法，行业内有的称之为水压爆破或水耦合爆破等，为区别于将药包置于受约束的有限水域中的传统水压爆破，本文将炮孔内药卷与水袋耦合装药爆破破岩的方法统一定义为水封爆破3。相对于空气介质，水是传播冲击波或应力波的极佳介质，水作为炮孔内耦合介质时产生更大的爆破裂缝区域5；利用水介质辅助爆破更有利于爆炸能量的传递，被爆岩石损伤分布更加均匀，损伤程度更高6。通过在钻孔底部填充水袋，不仅不会浸泡炸药产生毒害气体，且在加强岩体破碎效果和消除孔底残根等方面有着良好的应用效果7。因此，水介质与炸药耦合爆破对爆轰波和岩石裂纹的扩展有非常好的利用价值8。同时，通过调整水垫层与炸药的相对位置可获得不同的爆轰参数，适用于掏槽孔开拓临空面与周边孔光面爆破优化轮廓等不同功能9。与此同时，许多学者建立了水封爆破破岩数值分析模型12,57,911，分析了相关的破岩机理，也证明了数值分析方法在岩石爆破模拟中的可靠性，但有关水介质炸药耦合爆破如何影响裂隙扩展的认识仍然有待加深。水封爆破在大量997铁 道 科 学 与 工 程 学 报2023 年 3月工程实际中取得了良好的环保效果，其中，郭春等12总结了水封爆破对隧道施工降尘方面的技术应用。王轶君等13研究了隧道水封爆破对粉尘碳含量的优化效果。刘海波14研究了隧道聚能水压光面爆破相对于常规爆破的良好经济效果。郭春等15-16统计调研了交通隧道碳排放计算分析的研究现状，指出交通隧道碳排放量主要选用